Tau7 Serpentis
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Serpens |
| Right ascension | 15h 41m 54.7166s |
| Declination | +18° 27′ 50.531″ |
| Apparent magnitude (V) | 5.8 |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | A8Vam |
| U−B color index | +0.11 |
| B−V color index | +0.20 |
| R−I color index | +0.10 |
| Astrometry | |
| Radial velocity (Rv) | −31.38±0.12 km/s |
| Proper motion (μ) | RA: −61.654 mas/yr Dec.: +54.319 mas/yr |
| Parallax (π) | 18.7185±0.0408 mas |
| Distance | 174.2 ± 0.4 ly (53.4 ± 0.1 pc) |
| Absolute magnitude (MV) | +2.18 |
| Details | |
| Mass | 1.8 M☉ |
| Radius | 1.8 R☉ |
| Luminosity | 11 L☉ |
| Surface gravity (log g) | 4.20 cgs |
| Temperature | 7,809 K |
| Metallicity [Fe/H] | −0.02 dex |
| Rotational velocity (v sin i) | 78 km/s |
| Age | 839 Myr |
| Other designations | |
| τ7 Ser, 22 Serpentis, BD+18°3059, GC 21111, HD 140232, HIP 76878, HR 5845, SAO 101686, PPM 131613, WDS J15419+1828AB | |
| Database references | |
| SIMBAD | data |
Tau7 Serpentis, Latinized from τ7 Serpentis, is an A-type star in the constellation of Serpens, 174 light-years from the Earth. It has an apparent visual magnitude of approximately 5.804. It is a well-known Am star, a type of chemically peculiar star with unusually strong lines of heavier elements (metals) due to slow rotation and stratification of elements in the star's atmosphere.